A worked-example animation showing how impulse equals change in momentum for a ball that is caught, bounced straight back, or deflected at a right angle. Vector diagrams compare each case, including a component-based calculation for the perpendicular rebound, followed by a practice problem using J = FΔt to find final velocity. Useful for students learning to apply the impulse-momentum theorem to real collision scenarios.
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Scene 5: Solved Example (Ball & Bat/Wall Scenarios)Problem Statement: A ball of mass $6.0 \times 10^{-2}\text{ kg}$ moves east at $20\text{ m/s}$. Find the direction and magnitude of the impulse acting on the ball for: (a) When the ball is caught. (b) When it is hit to rebound west at the same speed. (c) When it is hit to rebound north at the same speed. Voiceover & Step-by-Step Breakdown:Formula: $J = \Delta p = p_f - p_i = m(v_f - v_i)$ (East is positive, West is negative). (a) When caught ($v_f = 0$): $J = (6.0 \times 10^{-2} \times 0) - (6.0 \times 10^{-2} \times 20) = \mathbf{-1.2\text{ N}\cdot\text{s}}$ (magnitude of $1.2\text{ N}\cdot\text{s}$ West). (b) When rebounding west ($v_f = -20\text{ m/s}$): $J = (6.0 \times 10^{-2} \times -20) - (6.0 \times 10^{-2} \times 20) = \mathbf{-2.4\text{ N}\cdot\text{s}}$ (magnitude of $2.4\text{ N}\cdot\text{s}$ West). (c) When rebounding north: Using vector components, the magnitude is $\mathbf{1.7\text{ N}\cdot\text{s}}$ directed to the Northwest. Scene 6: "Try It Yourself" ProblemsProblem Statement (A): A force of $5.0\text{ N}$ acts on a $4.0\text{ kg}$ body moving at $2.0\text{ m/s}$ for $2.0\text{ s}$ in the direction of its motion. (i) Impulse acting on the body: $J = F\Delta t = 5.0 \times 2.0 = \mathbf{10\text{ N}\cdot\text{s}}$. (ii) Increase in momentum: $\Delta p = J = \mathbf{10\text{ kg}\cdot\text{m/s}}$. (iii) Final velocity: $v_f = v_i + (\Delta p / m) = 2.0 + (10 / 4.0) = \mathbf{4.5\text{ m/s}}$. IMPORTANT LANGUAGE RULE: All on-screen text must be in Arabic EXCEPT mathematical equations, formulas, laws, symbols, variables, and numerical expressions. Keep every equation, formula, and law exactly as provided, without translating or changing it. Translate only the explanatory text, headings, labels, and descriptions into Arabic. Arabic text must use proper RTL direction and correct Arabic typography. Do not use English text anywhere else on the screen. Audience: student